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EvolutionAdaptation is characteristic which is inherited and improves an organisms ability to survive and reproduce over time.Prior to the theories of Charles Darwin and Jean-Baptiste Lamarck, people believed that species were fixed and simply could not change. People also commonly believed that the earth was no more than 10,000 years old.
Concepts on mechanisms for evolution have changed over time. Natural selection is a form of a mechanism for evolution, allowing only those that are the best fitted to their environment to survive. Originally, Lamarck proposed that organisms could evolve their physical characteristics within their own lifetime. Lamarck also proposed there was inheritance of acquired characteristics; meaning that, for example, a father who lifts weights will have a naturally muscular child. Both of these theories were later proved inaccurate when Darwin found that evolution and a physical change in an entire species characteristic takes a very long time to occur.
On the Voyage of the Beagle in 1831 Darwin discovered real life examples of descent with modification in South America. He found that there were numerous types of finches differing only in their beak types. The different beak types allow for each of the finches to survive in their unique environments. Between each South American island Darwin noted that the beak types differed slightly because each island had its own features which the finches had adapted to over time.

Examples of evidence for evolution include: Vestigial structures, embryo development, homologous and analogous structures, and the patterns in which organisms evolve.

• A vestigial structure is a part of an organism's body that was once used, but no longer has a true purpose or function. A human's appendix and a dogs dew claw are two simple examples of vestigial structures.



• During embryo development there are many obvious similarities during the growth stages. All vertebrates, for example, grow pouches on the side of their throats during one stage of development. In primal stages most embryos look very similar, changing drastically only later in the growth process.

Homologous structures are similar parts of an organisms which are seen in unrelated species. The forelimb of a human, flipper of a whale, and wing of a bat are all variations of a similar structure.

• Analogous structures are parts of two or more organisms which have developed similarly, yet have no actual relation. An example would be the wings of a bird and the wings of a butterfly. Both animals use the wings to fly, but there is no known connection between a bird and a butterfly.

Patterns of Evolution:

• During Convergent evolution unrelated species from similar environments develop similar features, which are called analogous structures.
• In Divergent evolution species of a common ancestor live in completely separate environments and therefore develop unique differences depending on the area the organism lives in.
• Adaptive Radiation - Species from the same ancestor survive by adapting to their specific environment.
• Co-Evolution - Two or more organisms within the same ecosystem that evolve in response to each other to achieve successful survival.
• Speciation - Development of an entirely new species. Example: Male donkey and female horse produce a mule, which is also sterile.

Choose the best answer:

1.What was the name of the voyage the Charles Darwin went on?
A. Bagel
B. Beagle
C. Birds
D. Bluetooth
E. Tacos
2. What species of birds did Darwin find in the Galapagos Islands?
A. Dodo Birds
B. Macaw
C. Finches
D. Pteradactyl
E. Bald Eagle
3. What are examples of Homologues Structures?
A. Fore arm of a Human and a Bat
B. Tail of a Dog and Leg of a Camel
C. Tongue of an Owl and Eye of a Shark
D. Foot of a T-Rex and a hand of a Sloth
E. A hard taco shell and a soft taco shell
4. During embryo Development all vertebrates grow what on the sides of their throat?
A. Legs
B. Eyes
C. Pouches
D. Fingers
E. A Baby
5. How many years did Darwin spend on his voyage?
A. 50
B. 38
C. 15
D. 6.9
E. 5
6. The theories of Evolution are what?
A. Always changing
B. Always the same
C. Very confusing
D. Not interesting
E. Unimportant to biology
7. Which of these is an example of a vestigial structure?

1. Hair on humans
2. Eyes on a bat
3. Dew claw on a dog
4. Claws on an eagle
5. Nose on a cat

8. Prior to Darwin’s theories, people believed the earth was how old?

1. 1 million years
2. 50,000 years
3. 12,000 years
4. 10,000 years
5. 552,000 years

9. Whose theories on evolution were commonly understood prior to Darwin’s?

1. Albert Einstein
2. Gregor Mendel
3. Buzz Aldrin
4. M. Taurasi
5. Jean Baptiste Lamarck

10. Which of these are examples of analogous structures?

1. Tail of a cat and hind legs of a lion
2. Whiskers of a cheetah and horns
3. Wings of a butterfly and wings of an eagle
4. Feet of a human and flippers of a whale
5. Eyes of a sloth and ears of a bat

11. What year did Darwin’s voyage begin on?

1. 1829
2. 1831
3. 1842
4. 1739
5. 1620

12. Evolution is which of the following?

1. An entirely accepted theory
2. A fact
3. A theory which is controversial to some
4. A myth
5. Not a modern theory